Renal Diseases Flashcards
What are the functions of the kidney?
- excretes waste substances
- acid-base balance
- Vit D activation
- blood pressure control
- red blood cell production
- regulate water balance
- regulates minerals in extracellular fluid
How do we measure kidney function?
- blood tests
- urine output
- elimination of radioisotopes
List some renal syndromes.
- asymptomatic proteinuria
- nephrotic syndrome
- haematuria
- acute kidney injury
- chronic kidney disease
Why is a kidney biopsy helpful?
- Provides a histological description that is compatible with a clinical condition
- May direct specific treatments.
Give some hypovolemic-related prerenal causes of kidney disease
Haemorrhage
Diarrhoea/ vomiting
Give some prerenal causes of kidney disease related to decreased perfusion.
Septic shock
Cardiac failure
Give some drug-related prerenal causes of kidney disease.
ACE inhibitors
Non-steroidal anti-inflammatory drugs
List some intrinsic renal diseases based on where they manifest.
GLOMERULAR:
- glomerulonephritis
TUBULAR:
- acute tubular necrosis
INTERSTITIAL:
- interstitial nephritis
What are some principles of glomerular disease?
- Whether it is primary or secondary, or if there’s a limited response to injury to the kidney
- Consider under headings of clinical syndrome, histopathology, and pathogenesis after taking personal, clinical and family history from patient
Why is glomerular disease a difficult subject?
- Often no good clinicopathological correlation
- Terminology is hard
- Ignorance of pathogenesis in many cases
What are the societal consequences of AKI?
- Significant impact on the outcome (hospital mortality/ post-discharge mortality)
- Drain on resources (length of stay in the ICU/ hospital referrals, tests, treatment, etc.)
- Affects patient morbidity (acute complications, dysfunction of other organs, risk of CKD)
How would you treat renal disease?
- General measures, such as dialysis, transplantation
- Psychosocial care
- Conservative management
- Identifying and treating the underlying condition.
Describe chronic renal management.
- conservative, with slow progression, to minimise symptoms and complication
- control Na+, water, BP
- regulate the diet (K+, phosphate, [protein])
→ IV Fe and erythropoeitin
What does dialysis achieve?
- removes nitrogenous wastes
- removes water
- corrects acid-base abnormalities
List the different types of deceased donors for transplantations.
Donors who died from cardiac death
Donors who were dead from ‘brain death’
List the different types of living donors for transplantations.
- Related donors (biological, emotional, social)
- Donors from kidney sharing schemes
- Altruistic donors
List the order of events that would occur in a hospital investigation if it was found that a patient may potentially have a low eGFR?
- Measure GFR
- Is there blood/protein in the urine?
- Is this intrinsic renal disease?
- Perform biopsy
- Provide general and specific treatments
- Manage consequences of poor eGFR (such as Vit D deficiency, lack of erythropoietin, dialysis, transplantation, conservative, etc.)
List the different ways in which we can measure kidney function, from the most accurate to the least accurate.
- Inulin (continuous infusion technique)
- Inulin (single bolus method), EDTA, iohexol
- 125l-iothalamate, DTPA
- 3-hour creatinine clearance with cimetidine
- estimated glomerular filtration rate (MDRD)
- serum creatinine
- 24-hour creatinine clearance
List some uremia-related cardiovascular risk factors.
- increased ECF volume
- calcification and calcium/phosphorus
- anaemia
- oxidant stress
- malnutrition
- pulse pressure
- triglycerides
- inflammation (C-reactive protein)
- sleep disorders
List some traditional coronary risk factors
- hypertension
- high LDL cholesterol
- smoking
- diabetes
- older age
- physical activity
- LVH (left ventricular hypertrophy)
What are the two forms of dialysis?
→ Haemodialysis
→ Peritoneal fluid
What is CKD a marker of?
→ cardiovascular risk
What are effects that indicate dialysis may be needed?
→ Oedema (pulmonary)
→ Hyperkalaemia
What is the first and second stage in AKI management?
FIRST:
→ Correct pre-renal factors
→ Relieve obstruction
SECOND
→ Maintain fluid and electrolyte balance
→ Nutrition
What is a cause of nephritic syndrome?
→ Post-streptococcal GN
What is rapidly progressive glomerular nephritis?
→ both modes of filter failure
→ Can advance in weeks or months
What are asymptomatic urine abnormalities and what is important in it?
→ blood or protein in urine
→ IgA nephropathy is important
What is nephritic syndrome?
→ Both filter failures
→ Abrupt onset
→ reduced GFR
→blood and protein in urine
What is nephrotic syndrome?
- Proteinuria
→ hypoalbuminaemia
→ Oedema (result of hypoalbuminaemia)
What are the two ways that the glomerulus can fail?
- Glomerulus filters things it shouldn’t or doesn’t filter things it needs to filter (reduced GFR)
What does it mean if the bleeding is in the urinary tract?
Possible cancer sign
What are 3 tubulointerstitial diseases?
→ acute tubular injury
→ acute tubulointerstitial nephritis
→ chronic tubulointerstitial nephritis
What are the 3 kidney compartments?
→ vascular
→ tubulointerstitial
→ glomerular
How is AKI measured?
→ changes in creatinine
What is long-term prognosis of acute kidney disease?
→ CKD
→ ESRF (end stage renal failure)
→ death
What happens in acute kidney injury?
→ Fluid retention - lymphoedema leads to pulmonary oedema
→ Hyperkalaemia - high K+ leads to cardiac arrhythmias
How do dysmorphic erythrocytes form?
Squeeze along the glomerular filter and become deformed
What does glomerular bleeding lead to?
→ Red cell casts in the urine
→ Red cells get stuck together and form the shape of the tubule
How is proteinuria quantified?
→ Urine albumin : creatinine ratio
→ Urine protein : creatinine ratio
How are glomerular diseases diagnosed?
→ Urine analysis
→ measures blood and protein
What does diabetes mellitus do to the kidney?
→ Chronic damage to kidney through high BP
What is chronic kidney disease?
→ Reduction in GFR that gets worse over time
What is haematuria?
→ blood in urine due to bleeding along the urinary tract
What causes asymptomatic proteinuria?
Error in filtration by glomerulus
What is creatinine and where is it produced?
→ biomarker for filtration of the glomerulus
→ skeletal muscle
